Strand testing



Dec. 28, 1948. I

s. L. ROSS STRAND TESTING Filed July 1'7, 1945 INVENTOR SAM/1 L ./?0.ss

ATTO RNEY Patented Dec. 28, 1948 Samuel L. Boss, New Brunswick, N. J., assignor to Johnson & Johnson, a corporation of New Jersey Application dill-y 17, 1945, Serial No. 605,480

6 Claims.

I 1 This invention relates to apparatus for testing the abrasion resistance of strands.

The utility and durability of fibrous articles,

such as thread, yarn, and various kinds of texorder to determine in advance the durability of fibrous articles made from various materials, it has been proposed to testthe abrasion resistance of the yarns before constructing the article in order to assist in the selection or themost desirable materials. Devices which have come to my attention fortesting the abrasion resistance of yarns have the disadvantage that they do not accurately simulate the conditions of actual use I of many fibrous materials and in particular they do not "abrade the yarns, or the individual fibers,-

or monofilaments of which the yarns are composed, across the length of the fiber .or monofilament and do not properly compress the fibers or monofilaments while abrading the yarn.

Accordingly it is an object of my invention to provide .a simple and effective-device for testing yarns, monofilaments and the'like .by subiecting the yarns, for example, to a combination of tension and transverse abrasion which accurately simulates the forces applied to the yarns in many instances of actual use.

Another object of the invention is to provide a simple apparatus which can be set in operation and thereafter automatically test and record the characteristics of the fiber without further attention.

The single figure of the accompanying drawing is a perspective view, partly diagrammatic, of one form of apparatus embodying my invention.

The invention is illustrated as applied to a device which is particularly adapted to testing dental floss and for simulating the conditions under which dental floss is used, although this identical apparatus is equally well suited for the testing of other fibers and yarns for other purposes.

Referring to the drawing, two opposed friction members and 12 are suitably mounted and supported to be resiliently urged in contact with each other, and a fibrous strand I4 is so supported that it can be moved back and forth between the friction members. As illustrated the friction members have surfaces which converge toward the point of contact and simulate the cusps of the crown of a tooth, having roundv 2 ed polished surfaces to be engaged by the strand. The friction members may be of any suitable material, such as, hardened and polished steel or if desired actual teeth can be used. The term "tooth cusp as herein used is intended to cover either a natural tooth or a simulated tooth cusp.

The member [2 is mounted on a stationary support and the member 1!] is mounted on a movable support 46 which may slide in guides 18 and is resiliently urged against the member l2 .by the weight of the support I 8 which may be suitably adiusted by any desired number of weights 2.0, .22, and .24. A bracket 26, having an opening 21, supports an arm 28 having an opening 311 through which openings the strand to be tested passes. "One end of the strand is anchored in any suitable manner to a slide 32 on a guide rod 34 supported in any suitable manner as by supports 36 and 38. The tension of the strand is adjusted by any suitable number of weights 4B and 42 supported on a rod 44 which is supported by the other end of the strand. When the strand is mounted, as shown, the slide .32 is moved back and forth on the rod -34 causing the strand, while held under tension, to pass between the cusps. l0 and I2 which both compress the strand and abrade it in a .direction transverse to its length. It has been found that number of times a strand withstands passage between the cusps 1.4] and I2 yarns, the cusps can be made of porcelain, wood,

metal, or other material which performs representative tests.

It has been found that the number of times a single strand or yarn will pass between a given pair of compression members under given conditions furnishes a more accurate index of the wearing qualities of certain fabrics than any other means of testing which has come to my attention. Consequently the term strand or fibrous strand as used herein is intended to include an individual fiber, a monofilament of syn- 3 thetic material, and a yarn or thread twisted or braided from individual fibers.

Preferably the slide 32 is repeatedly operated by a pitman 46 driven by any suitable motor 48, for example an electric motor having a reduction gear. The motor is started and stopped by a switch 50 operated by a switch arm 52 connected tothe' weight rod 44 so that when the strand breaks in test the motor is automatically stopped. Any suitable counter 54 may be mounted in the path of the slide 32 to register the= number of times the strand passes between the abrasion members.

I claim as my invention: v i

1. Apparatus for testing the abrasion resistance of a fibrous strand comprising in combination means for holding a strand, a pair of op-' posed members including a tooth cusp adapted to compress the strand and to yieldingly resist passage of the strand between said members and means for effecting relative movement between the strand and the members in'a direction transverse to the length of the strand to cause the strand to be compressed and to pass between the members while under tension.

2. Apparatus for testing the abrasion resistance of a fibrous strand comprising in combination means for holding a strand, a pair of opposed members including a tooth cusp adapted to compress the strand, means for resiliently urging the members toward one another to yieldingly resist passage of the strand between said members, and means for effecting relative movement between the strand and the members in a direction transverse to the length of the strand to cause the strand to be compressed and to pass between the members while under tension.

3. Apparatus for testing the abrasion resistance of a fibrous strand comprising in combination means for holding a strand, a pair of opposed members adapted to compress the strand, one of said members being a tooth cusp, means for resiliently urging the members toward each other, and means for moving one end of the strand in a direction transverse to its length to cause the strand to pass between the members while the strand is held under tension.

4. Apparatus for testing the abrasion resistance of a fibrous strand comprising in combination means for holding a strand, a pair of opposed 4 members adapted to compress the strand, one of said members being a tooth cusp, means for resiliently urging the members toward each other, and means for moving one end of the strand n a direction transverse to its length to cause the strand to pass between the members while the strand is held under tension, said holding means "beingadapted to maintain the strand tension substantially constant during said movement.

5. Apparatus for testing the abrasion resistance of fibrous strands comprising in combination means for holding a strand, a pair of opposed members adapted frictionally to engage opposite sides of" the strand, means for yieldingly urging the members toward each other to compress the strand and to yieldingly resist passage of the strand between the members, and means for repeatedly passing the strand between the members in a direction transverse to the length of the strand to compress and abrade the strand under tension.

6. Apparatus for testing the abrasion resistance of fibrous strands comprising in combination means for holding a strand, a pair of opposed members adapted to engage opposite sides of the strand, means for yieldingly urging the members toward each other to yieldingly resist passage of the strand between the members, the members having converging surfaces adapted to progressively compress the strand when the strand is passed between them, and means for passing the strand between the members in'a direction transverse to the length of the strand progressively to compress and abrade the strand while SAMUEL L. Ross.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 889,993 Vaughan et al. June 9, 1908 2,018,971 Paume Oct. 29, 1935 2,079,591 Bartell May 11, 1937 2,292,577 Mahannah Aug. 11, 1942 2,372,093 Leape et a1 Mar. 20, 1945 2,373,115 Graves Apr. 10,1945 2,397,227

Wilhoyte, Jr Mar. 26, 1946 

